Bipack color film containing nondiffusing color formers and processing thereof



March 29, 1955 v TULAGlhl 2,705,200

BIPACK COLOR FILll/I CONTAINING NON-DIFFUSING COLOR FORMERS AND PROCESSING THEREOF Filed NOV; 15, 1950' Fig. l.

7 Blue sensitive halide emulsion layer containing an open chain colloidal silver keto methylene compound as tilter layer yellow color former -0000.000000000000000 "oof.fofofofofofofofofofofofofofofof Base Mixture of green and red seneitive silver halide emulsion: containing as a common color former for magenta and cyan,

- a phenol capable of coupling para to the phenolic group and being non-diffusing in' the emulsions Blue sensitive halide emulsion layer containing an open chain Colloidal sihier keto methylene compound as filter layer 7 yellow color former ailg liihiiiitiiikigg 371/ ,IYJMIIIIVIII d c Hardened red and green Unhardened gelatine containing sensitive'eilver halide as color former for magenta emulsions and cyan, a phenol capable of coupling mm to the phenolic group and being non-diffueing in gelatine fiageefi ATTORNEYS United States Patent Vsevolod Tulagin, Phillipsburg, N. eral Aniline & Film Corporation, corporation of Delaware Application November 15, 1950, Serial No. 195,763 12 Claims. (Cl. 95-2) J., assignor to Gen- New York, N. Y., a

The present invention relates to bipack color film containing non-diffusing color formers, and capable of being processed to yield the three subtractive color images, and the method of processing such bipack.

Most color film sold today is in the form of a tripack, involving, as it does, a base upon which are coated three emulsion layers sensitive to the red, green and blue regions of the spectrum, respectively, and with filter layers interposed between the three emulsion layers.

The production of such film is quite expensive, due to the necessity of casting so many thin emulsion and filter layers. It is evident that the cost of such production could be considerably reduced if it were possible to exploit color film in the form of a mono-layer or a bipack film.

The use of bipack color films has been suggested, but in such film the emulsions were free from color formers. The films were constituted by a base on which is cast a green, red and blue sensitive emulsion, over this a yellow filter and over the yellow filter a blue sensitive emulsion. Color separation was obtained in this material by selective exposure to one region of the spectrum, followed by a color development after each exposure.

Thus the film is exposed to an original to be copied, through a red filter and developed in a p-dialkylamino aniline developer containing a color former capable of yielding a cyan dye image with the oxidation products of such developer. The film is washed and again exposed to the original through a green filter, after which it is developed in a p-dialkylaminoaniline developer containing a color former for the magenta image. Finally, the film is exposed to white light and developed with a p-dialkylaminoaniline color developer containing a color former for the yellow image. It is evident that in the processing of a bipack constituted as above, three separate selective exposures and three separate color developments are necessary.

This procedure is not possible with a bipack in which the silver halide emulsion layers contain color formers and in which the usual p-dialkylaminoaniline developers are employed. Manifestly, the bottom layer of such a bipack which is sensitive to green and red would have to contain two color formers, one for the cyan image and one for the magenta image. Inasmuch as these two color formers would be intimately mixed, no color separation could possibly be obtained.

I have now provided a bipack which does permit the use of the color formers in the emulsion layers, and which is capable of being processed by the selective exposure and color development method to three subtractive colored images. My procedure has not only the advantage of cheapness by virtue of the film employed, but also by virtue of the fact that only two selective exposures and color developments are necessary.

Bipack film containing color formers capable of yielding the three subtractively colored images and the method of processing such film by two selective exposures and color developments constitute the purposes and objects of the present invention.

The usual color developers for the processing of commercial color film are of the p-dialkylaminoaniline type, a representative example of which is p-diethylaminoaniline. The oxidation products of these developers combine with color formers containing an open-chain methylene group, such as an acetoacetanilide, to yield yellow azomethine dye images, with color formers containing a closed-chain active methylene group, such as a pyrazolone, to yield 2,705,200 Patented Mar. 29, 1955 magenta azomethine dyestuff images, and with a phenol having a reactive para position to form cyan quinoneimine dye images.

United States Letters Patent 2,486,440 granted on November l, 1949, to Willy A. Schmidt and Vsevolod Tulagin describes the production of azine dye images by utilization, as color developers, of 2,4-diaminoanilines. My invention is based upon the observation that color formers of the phenolic type, having a reactive coupling position para to the hydroxyl group and being unsubstituted or substituted by a replaceable group meta to the phenolic hydroxyl group, while reacting with the oxidation products of color developers of the p-dialkylaminoaniline type to yield cyan dye images, react with the oxidation products of 2,4-diaminoanilines to yield brilliant magenta dye images.

Based upon this observation, I conceived the possibility of utilizing the same phenolic color former to produce a magenta dye image through development with a 2,4- diaminoaniline and to produce a cyan dye image through development with a p-dialkylaminoaniline. This conception is further predicated upon the fact that the openchain ketomethylene color formers react with both the oxidation products of the p-dialkylaminoaniline developers and with the oxidation products of 2,4-diaminoaniline developers, to yield yellow dyestufi images.

Proceeding from the above, I constructed a bipack by casting on a base, a mixture of a green and red sensitive emulsion, each containing the same phenolic color former, over such emulsion layer a yellow filter layer, and over the yellow filter layer, a blue sensitive emulsion containing an open-chain ketomethylene compound.

I also constructed, as an alternate, a bipack in which the emulsion layer cast upon the base was a panchromatic emulsion containing the phenolic color former. In other words, my bipack envisages a film in which the lowermost layer, i. e. that cast upon the base, is a silver halide emulsion, sensitized for both the red and green regions of the spectrum.

The phenolic color former which I employ in the lowermost layer must be one in which the position para to the phenolic hydroxyl group is unsubstituted or is substituted by a replaceable substituent such as chlorine, bromine or a sulfonic acid group, and the position meta to the phenolic hydroxyl group is unsubstituted or substituted by a halogen.

Inasmuch as such color formers are to be used in the emulsion, they must contain a radical which renders them fast to difiusion m such emulsion. Preferably, the color formers which I employ are alpha naphthols or alpha quinolines, i. e. 8-hydroxyquinolines containing a group rendering them fast to diffusion.

Examples of compounds suitable for my purpose are to be found in United States Letters Patents 2,156,821, 2,324,832, 2,343,051, the application of Winfred C. Craig, Serial No. 745,113, filed April 30, 1947, now Patent No. 2,530,349, entitled Cyan Color Formers Capable of Yielding Fine Grained Images, United States Letters Patents 2,524,741 and 2,524,725, and the naphthol couplers of United States Letters Patent 2,186,849, specifically l stearoylamino-4-a-hydroxy-naphthoylaminobenzene-3-sulfonic acid, 1-laurylamino-4-a-hydroxy-napthoylamino naphthalene-6-sulfonic acid, l-octadecylamino-4-ahydroxy-naphthoylaminobenzene-3-thiosulfonic acid, N-

octadecyl-1-hydroxy-2-naphthoylamide, N oleyl a hydroxynaphthoic acid amide, and the like.

Other examples of such non-diffusing phenols are the following:

OH III-Claim @o ONHU l smH 4-N-methyl-N-octadecylamino-3-(1-hydroxy-2-naphthoy1) aminobenzenesulfonlc acid a blue and green filter,

U m N 4;

1-octadecyl-2 [2-(1-hydroxy) -naphthyl] -benzimidazolefi-sulfonic aci CuHzr-NCH;

on o N EN- 4-N-methy1-N-octadecylamino-3 (4methyl-6-chl0ro-S-hydroxyqulnaldoyl)-aminobenzenesulfonic acid 2 (m -benzoylacetamidophenyl)-1-octadecyl-5-benzimidazole sulfonic acid,

3-stearoylamino-5-sulfoacetanilide,

3,3 ureylenebis 6-p-benzoyl-acetamidobenzoamidobenzene sulfonic acid,

2 p-benzoylacetamidobenzamidostearoylamino-p-toluene sulfonic acid,

pyanoacetyl-3-octadecenyl succinalic acid,

and the like. i

The yellow filter such as filter layer may be any conventional yellow of colloidal silver or of a dyestufi which discharges in the photographic processing baths, such as tartrazine or the like.

Film constituted as above may be utilized in the following manners:

(A) The film is exposed to an original through a red filter and developed with a developer of the p-dialkylaminoaniline class, such as p-diethylaminoaniline. Such development produces a cyan image in the red sensitive emulsion. The film is then exposed to the original through a cyan filter or consecutively through a blue and green filter and developed with a 2,4-diaminoaniline developer of the type described in United States Letters Patent 2,486,440, or in the aforesaid copending application, Serial No. 101,913 of Robert C. Gunther.

(B) The film is exposed to an original through a red filter and developed with a developer of the p-dialkylaminoaniline class such as p-diethylarninoaniline. Such development produces a cyan image in the red sensitive emulsion. The film is now bleached with a bleach containing potassium or sodium ferricyanide and potassium bromide in the conventional manner. The excess oxidizing agent is removed by treatment with a dilute aqueous sodium sulfite bath. The film is then exposed to the original through a cyan filter, or consecuctively through and developed with a 2,4-diarninoaniline developer of the type described in U. S. Patent 2,496,404 or in the aforesaid copending application, Serial No. 101,913 of Robert C. Gunther.

The second development step in procedures A or B produces azine yellow and magenta dye images in the blue sensitive and green sensiuve emulsions. Consequently, there is obtained a-negative image in the three subtractive colors after bleaching and. fixing to remove the silver and unused silver halide.

(C) The above film may be exposed to the original through a green filter and developed with a 2,4-diamiuoaniline, to produce a brilliant magenta image in the green sensitive emulsion. The film is then exposed to the original through a magenta filter, or consecuctively through a red and blue filter and developed with a developer of the p-dialkylaminoaniline class, such as p-diethylaminoaniline, to produce a yellow azomethine dye image in the outermost layer, and a cyan quinoneimine dye image in the red sensitive layer. By removing the silver and silver halide through bleaching and fixing, a negative containing the three subtractively colored images is obtained.

As in the above example, it may at times be desirable to convert the silver images obtained by the first development to silver halide by treatment with conventional ferricyanidebromide bleaching solutions, and then remove the excess oxidizing agent with dilute aqueous solutions of sodium sulfite prior to the second exposure.

(D) The procedures outlined, as is evident, permit the formation of negative images by the copying of an original. I have also used my invention for the preparation of positive subtractively colored images by the reversal process.

To this end, I constructed a film as follows. A red sensitive silver halide emulsion is treated with a gelatin tanning agent, such as formaldehyde, formaldehyde glyoxal, or the like, to thoroughly harden the gelatin thereof. A green sensitive silver halide emulsion is similarly hardened. The two hardened emulsions are thoroughly shredded and ground to a size of about 1 to 2p in diameter, and suspended in unhardened gelatin containing a phenolic coupler fast to diflusion, of the type mentioned above. The resulting product is then cast upon a base, and over it is cast a yellow filter layer, and over that a blue sensitive silver halide emulsion containing a yellow color former of the open-chain ketomethylene type which is fast to diffusion in the emulsion.

The film constituted as above is exposed to an original, and developed in a black and white developer. The is then re-exposed to red light so that all of the red sensitive emulsion granules are completely exposed, after which the film is developed with a p-diethylaminoaniline developer. This development produces a cyan image in the red sensitive emulsion granules; The film is washed and then exposed either to white light or to green and blue light, either simultaneously or in sequence, and developed in a developer of the 2,4-diaminoaniline type. This development produces a magenta image in the green sensitive emulsion granules and a yellow image in the blue sensitive emulsion granules. The film is then bleached and fixed to yield a brilliant positive in the three subtractive colors.

As a modification of the procedure outlined above, the film, after the black and white development, is completely exposed to green light and developed in a 2,4-diaminoaniline developer. This produces a brilliant magenta azine dye image in the green sensitive silver halide particles.

After washing, the film is exposed either to white light or to blue and red light simultaneously, or in sequence. The film is then developed in a p-diethylaminoaniline developer, to yield a yellow azomethine dye image in the blue sensitive layer and a cyan quinoneimine dye image in the red sensitive silver halide granules. By bleaching and fixing, there is obtained a brilliant positive containing the three subtractively colored images.

The invention will be further explained by reference to the following examples, and the attached self-explanatory drawing, Fig. 1 of which discloses, in section, a bipack designed to produce, by copying, a subtractively colored negative; and Fig. 2 of which discloses, in section, a bipack designed to produce a subtractively colored positive by reversal.

Example 1 A film as shown in Fig. 1 is formed by dispersing in a green sensitive silver bromide emulsion 15 grams per kilo of emulsion, 4 N-ethyl-4-N-octadecylamino-3-(1- hydroxy-Z-naphthoyl)-aminobenzene sulfonic acid, and in a red sensitive silver bromide emulsion the same quantity of the same compound, mixing the two emulsions and casting them on a base. Over the emulsion layer there is then cast a colloidal silver filter layer and over this layer a blue sensitive silver bromide emulsion layer containing 25 grams per kilo of emulsion, of 2-(benzoylacetamidophenyl)-1-octadecyl-5-benzimidazole sulfonic acid.

The film is then exposed to original through a red filter and is developed at 68 F. with a developer of the following constitution:

Grams p-Aminodiethylaniline HCl 4 Sodium sulfite Hydroxylamine HCl 2 Sodium carbonate 40 Potassium bromide 1 Water to make up 1 liter.

The film is washed forfive minutes in running water at 68 F. and is then exposed to the original through a cyan filter and developed at 68 F. with a developer of the following constitution:

Grams 6-phenylamino-4-(fl-hydroxyethylamino) metanilic- 8 acid Potassium carbonate Sodium sulfite 60 Potassium bromide 10 Benzylamine .5

Water to 1000 cc.

The film is washed, bleached in a ferricyanide bleach, and fixed in an acid hardening hypo solution. There is thus obtained a negative film containing a cyan quinoneimine dye image, and yellow and magenta azine dye images. In other words, the original bipack has been processed to the three subtractively colored images by two selective exposures and color developments.

Example 2 A bipack depicted as in Fig. 2 is prepared as follows: A red sensitive silver bromide emulsion is thoroughly hardened by treatment with formaldehyde glyoxal, and a green sensitive emulsion is hardened in the same way. The two emulsions are thoroughly shredded to granules of a size ranging from about 1 to 2p. in diameter.

There is dispersed in unhardened gelatin, grams per kilo of the gelatin, of 4-N-methyl-N-octadecylamino- 3 (4 methyl 6 chloro 8 hydroxy quinaldoyl)- amino-benzene sulfonic acid, and the two hardened and granulated emulsions are suspended therein. The resulting emulsion is then cast on a support and over it is cast a yellow colloidal silver filter layer, and over that a blue sensitive silver bromide emulsion containing 30 grams per kilo of emulsion, of 3-stearoylamino-5-sulfoacetoacetanilide.

The bipack is exposed to twelve minutes at 68 white developer of the an original and developed for following constitution:

Grams p-Methylaminophenol sulfate 3 Sodium sulfite Hydroquinone 6 Sodium carbonate (monohydrate) 40 Sodium thiocyanme 2 Potassium bromide 2 Water to make up 1 liter.

The film, after development, is washed in running water at 68 F. and then exposed to red light so that all of the red sensitive emulsion granules are completely exposed. The film is then developed in the p-diethylaminoaniline developer of Example 1, and then washed in running water at 68 F. and completely exposed to white light. The film is then developed in the 2,4-diaminoaniline developer of Example 1.

The film is then bleached with a ferricyanide bleach and fixed with There is thus obtained a brilliant positive in the three subtractive colors.

Modifications of the invention will occur to persons skilled in the art and I, therefore, do not intend to be limited in the patent granted except as necessitated by the appended claims.

I claim:

1. A multilayer material for producing color images in the three subtractive colors, to wit, yellow, magenta and cyan, comprising a base and only two sensitive emulsion layers, one emulsion layer containing two differently color sensitized groups of silver halide grains sensitized respectively for green only and for red only located on the said base, said layer containing as the sole color former a phenolic compound capable of coupling para F. with an energetic black and an acid hardening fixing bath and washed.

lit

to the phenolic hydroxyl group and being substituted meta to said hydroxyl group by a member of the class consisting of hydrogen and a substituent replaceable on color development and being fast to diffusion in the emulsion, said green sensitized silver halide grains when exposed yielding a'magenta dye image upon development with a 2,4-diaminoaniline developer and said red sensitized silver halide grains when exposed yielding a cyan dye image upon development with a p-dialkylaminoaniline developer, a yellow filter layer on said silver halide emulsion layer, and a blue sensitive silver halide emulsion layer on said yellow filter layer, said latter emulsion layer containing as a color former, an open chain ketomethylene compound fast to diffusion in said emulsion.

2. The bipack as defined in claim 1 wherein the phenolic color former is an alpha naphthol.

3. The bipack as defined in claim 1 wherein the color former is an S-hydroxyquinoline.

4. A bipack for producing color images in the three subtractive colors to wit, yellow, magenta and cyan comprising a base, an unhardened gelatin layer on said base containing as the only color former a phenolic color former capable of coupling para to the phenolic hydroxyl group and being substituted meta to said hydroxyl group by a member of the class consisting of hydrogen and a substitucnt replaceable upon color development, and being fast to diffusion in the gelatin, said unhardened gelatin layer having suspended therein, hardened granules of a red sensitive silver halide emulsion and hardened granules of a green sensitive silver halide emulsion respectively, a yellow filter layer on said gelatin layer and a blue sensitive silver halide emulsion containing as the color former an open-chain ketomethylene compound 1fast to diffusion in said emulsion on said yellow filter ayer.

5. The bipack as defined in claim 4 wherein the phenolic color former is an alpha naphthol.

6. The bipack as defined in claim 4 wherein the phenolic color former is an 8-hydroxyquinoline.

7. A method of processing the bipack of claim 1 to the three subtractive color images which comprises exposing the bipack in any sequence selectively to red and green light, developing the bipack after the exposure to red light with a color developer of the p-dialkylaminoaniline class, and developing the bipackf after the exposure to green light with a developer of the 2,4-diaminoaniline class.

8. The process as defined in claim 7, wherein the developer of the 2,4-diaminoaniline class is 6-phenylamino- 4-( 8-hydroxyethylamino)metanilic acid. f: V

9. A method of processing the bipack of claim 4 to a positive containing the three subtractively colored images which comprises exposing the bipack, developing the bipack in an energetic black and white developer, reexposing the bipack to a light which selectively renders developable the hardened silver halide emulsion granules sensitized to light of one region of the spectrum, developing the bipack in a color developer selected from the class consisting of a p-dialkylaminoaniline and a 2,4-diaminoaniline, the 2,4-diaminoaniline developer being used when the re-exposure affects the hardened silver hal ide emulsion granules sensitized to green light, and the p-dialkylaminoaniline being used when *the re-exposure affects the hardened silver halide emulsion granules sensitized to red light re-exposing the bipack to light which renders developable the blue sensitive emulsion and the unexposed hardened silver halide emulsion granules, and developing the bipack in a developer selected from the class consisting of a p-dialkylaminoaniline and a 2,4-diaminoaniline, the development being with a p-dialkylaminoaniline when the first development is efiected with a 2,4-diaminoaniline developer and with a 2,4-diaminoaniline when the first development is effected with a pdialkylaminoaniline developer.

, 10. A method of processing the bipack of claim 1 to the three subtractive color images which comprises exposing the bipack through a red filter, developing the bipack with a color developer of the p-dialkylaminoaniline class, re-exposing the bipack through a cyan filter and developing the same with a developer of the 2,4-diaminoaniline class.

11. A method of processing the bipack of claim 1 to the three subtractive color images which comprises exposing the bipack through a red filter, developing the same with a developer of the p-dialkylaminoaniline class,

suhjeftfing the lzlipackd to a hleacllia contdaining an alkali References Cited in the die of this patent meta erricyani e an potassium romi e, removing e excess oxidizing agent, re-exposing the bipack through a UNITED STATES PATENTS cyan filter and developing the same with a 2,4-diamino- 1,954,452 Mannes et al. L Apr. 10, 1934 aniline developer. 6 1,996,928 Mannes et al. Apr. 9, 1935 12. A method of processing the bipack of claim 1 to 2,168,182 Wendt Aug. 1, 1939 the threie1 slllabtl'fltlflvgr 601%! images glhich dcorrilprises egr- 2,I68,183 Wilmanns et a1 Aug. 1, 1939 posing t e ipac t oug a green ter, eve oping e same with a 2,4-diaminoaniline developer, re-exposing FOREIGN PATENTS the bipack through a magenta filter and developing the 10 446,392 Great Britain Apr. 29, 1936 same with a developer of the p-dialkylaminoaniline class. 448,161 Great Britain June 3, 1936 513,234 Great Britain Oct. 6, 1939 

1. A MULTILAYER MATERIAL FOR PRODUCING COLOR IMAGES IN THE THREE SUBTRACTIVE COLORS, TO WIT, YELLOW, MAGENTA AND CYAN, COMPRISING A BASE AND ONLY TWO SENSITIVE EMULSION LAYERS, ONE EMULSION LAYER CONTAINING TWO DIFFERENTLY COLOR SENSITIZED GROUPS OF SILVER HALIDE GRAINS SENSITIZED RESPECTIVELY FOR GREEN ONLY AND FOR RED ONLY LOCATED ON THE SAID BASE, SAID LAYER CONTAINING AS THE SOLE COLOR FORMER A PHENOLIC COMPOUND CAPABLE OF COUPLING PARA TO THE PHENOLIC HYDROXYL GROUP AND BEING SUBSTITUTED META TO SAID HYDROXYL GROUP BY A MEMBER OF THE CLASS CONSISTING OF HYDROGEN AND A SUBSTITUENT REPLACEABLE ON 